Water-tube boiler.



Patented Sept. 17, 1912.

2 SHEETS-SHEET 1.

WITNESSES TO A. P. YARROW.

WATER TUBE BOILER.

APPLICATION FILED APR.17,1911.

Patented Sept. 17, 1912.

2 SHEETS-SHEET 2,

WITNESSES INVENTOR MQWA ALFRED FERNANDEZ YARROW, OF SCOTLAND, NEWBRUNSWICK, CANADA.

WATERrTUBE BOILER.

Specification of Letters Patent.

Application filed April 17, 1911. Serial No. 621,566.

Patented Sept. 1'7, 1912.

To all whom it may concern:

Be it-known that I, ALFRED FERNANDEZ Yxnnow, a subject of the King ofGreat Britain, residing in Scotland, New Brunswick, Canada, and whosepost-ofiice address is Campsie Dene, Blanefield, in the county ofStirling, Scotland, New Brunswick, engineer, have invented certain newand useful Improvements in Water-Tube Boilers, of which (the followingis a specification.

This invention relates to water .tube boilers of the type in which asteam and water drum is connected by sets of downwardly extending tubeswith two water drums, one on each side of the combustion space of theboiler furnace the gases from which pass divcrgently right and leftthrough the respective sets of water tubes to a divided uptake or toseparate uptakes. According to the present invention such water tubeboilers are fitted with a superheater which is placed on one side onlyof the boiler so that the portion of the furnace gases which passes fromthe combustion space to that side flows through the superheater and theset or sets of water tubes arranged on that side, while the remainingport-ion of the gases passes to the side of the boiler and flows onlythrough the set or sets of water tubes on the last named side. Suchwater tube boilers are also fitted with means for varying the flow ofthe gases through the superheater, the arrangement being such that thesuperheater may be at once put entirely out of action so that, forexample, if there is a sudden stoppage of the engines the superheatertubes may be prevented from being burned out. The superheater tubes arepreferably disposed on the'farther side of the generator or water tubesin the direction of the flow of the gases, or interposed in a gap leftwithin the bank of water tubes, the ends of these superheater tubesbeing expanded into steam chambers one of which is in communication withthe steam space of the steam drum, while the other is in communicationwith the steam distributing pipe or pipes or with the steam stop valve.

The How of the furnace gases through the bank of generator tubes on oneside of the boiler and through the superheater on the same side iscont-rolled by means of a damper preferably placed in the boiler funnelwhich is for this purpose divided centrally by means of a partitionextending upwardly from the bottom of the uptake to a point beyond thedamper; alternatively there may be separate funnels or uptakes for thetwo sides of the boiler, that on the superheater side being providedwith a damper by which the flow of the furnace gases on that side maybe'varied or entirely arrested. The damper may be hollow and cooled byintroducing air into it through a hollow spindle, the supply of airbeing drawn from any suitable source, as for-example, from thestokehold, or the delivery side of the forced draft fan, air outletsbeing provided to the damper, preferably toward the extremity thereof.

The invention is illustrated in the accompanying drawings as applied toa water tube boiler of the Yarrow type, Figure 1 being a somewhatdiagrammatic cross section of such a boiler showing one arrangement ofsuperheater and controlling damper, and Fig. 2 a view showing anotherdisposition of the super-heater.

In these drawings 1 is a steam and water drum, 2 and 2 the water drums,3 and 3 the banks-of generator tubes connecting the steam drum with thewater drums, a the superheater tubes, 5 and 5 steam chambers into whichthe tubes are expanded, G the hollow damper placed in the uptake on oneside of the funnel 7 which is divided by a partition 8. The air is shownas supplied from the stokchold 9 by pipe 10 which is in connection withthe hollow spindle 6 of the damper 6.

Although baflles other than the fixed baflle plates 11 are not shown inthe drawing, it will be understood that the distribution of the hotgases on their passage from the CQlIlbustion chamber 12 to the uptakemay be controlled by any suitable arrangement of bafiles applied eitherto the generator tubes 3 or to the superheater 4, or to both.

It will be seen (as shown in Fig. 1) that on that side of the boilerwhich is fitted with the superheater, the bank of generator tubes mayhave fewer rows and the water drums associated therewith be of lesscapacity than the corresponding tubes and drum on the other side of theboiler, the object being to secure substantially equal resistance to theflow of the gases along the two sides.

It will be understood that any suitable arrangment of baflles may beprovided for insuring a proper distribution of the furnace gases amongthe generator tubes and such arrangement of battles might involve thediversion past the superheater of part of the furnace gases traversingthat side of the boiler, but even in this case the gases which traversethe superheater must also pass among the generator tubes on the sameside.

Having thus described the nature of this invention and the best means Iknow of carrying the same into practical effect, I claim I 1. Thecombination with a water tube boiler having av steam and water drum, apair of water drums one on each side of the combustion space of theboiler furnace and sets of downwardly extending water tubes respectivelyconnecting the steam and water drum directly with the water drums, of asuperhcater comprising a number of tubes and arranged on one side onlyof the said combustion space, uptakes located one on each side of thesteam drum, one of the uptakes adapted to receive the gases passing fromthe combustion space through the superheater and the water tubesdisposed on one side'of the steam and water drum and drum directly withthe water drums, of a superheater comprising a number of tubes andarranged on one side only of the said combustion space, uptakes locatedone on each side of the steam drum, one of the uptakes adapted toreceive the gases passing from the combustion space through thesuperheater and the water tubes disposed on one side of the steam andwater drum and the second uptake adapted to receive the gases traversingthe water tubes on the other side of the steam and water drum,

and a damper fitted within the first said uptake whereby the flow ofgases through the 59 of a superheater comprising a number of tubes andarranged on one side only of the said combustion space, uptakes locatedone on; each side of the steam' drum, one of the upt-akes adapted toreceive the gases passing from the combustion space through thesuperheater and the water tubes disposed on one side of the steam andwater drum and the second uptake adapted to receive the gases traversingthe water tubes on the other side of the steam and water drum, a damperfitted within the first said uptake whereby the flow of gases throughthe superheater and the water tubes associated therewith may becont-rolled, and means for aircooling said damper.

4. A water tube boiler coinprising an upper steam and water drum, twolower water drums oneon each side of the furnace, two sets of watertubes one on each side of the furnace connecting the upper drum with therespective lower drums, separate up takes for the "furnace gasestraversing the respective sets of water tubes, a supcrhcater on one sideonly of the furnace in the path of the gases to the uptake on that sideand a damper in the said uptake whereby the furnace gases can bediverted from the superheater when desired and the steam generatingcapacity of the boiler simultaneously reduced.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

ALFRED FERNANDEZ YARROW.

Witnesses:

JOSEPH MLLLARD, W. I. SKERTEN.

